JANUARY 18, 2011

Kids Who Don’t Sleep Enough Are at Greater Risk for Depression, Anxiety Later

By ANDREA PETERSEN

Every parent knows that a tired kid is a cranky kid. Now, scientists are discovering that children with chronic sleep problems are at increased risk for developing a mental illness later in life.

Recent studies show that children who have persistent sleep problems, such as difficulty falling asleep or staying asleep, or not getting enough night-time shut-eye, are more likely later to suffer from depression and anxiety disorders and to abuse alcohol and drugs than kids without sleep problems. The findings add to previous research that has linked children’s sleep problems to a host of issues, including aggressive behavior, learning and memory problems and obesity.

A 2010 study of 392 boys and girls published online in the Journal of Psychiatric Research found that those who had trouble sleeping at 12 to 14 years old were more than two times as likely to have suicidal thoughts at ages 15 to 17 as those who didn’t have sleep problems at the younger age. In a study published last year in Alcoholism: Clinical and Experimental Research, involving 386 participants, children whose mothers reported that they were overtired when 3 to 8 years old were 2.8 times as likely to binge drink when they were 18 to 20 years old. And a study of 1,037 children revealed that 46% of those who were considered to have a persistent sleep difficulty at age 9 had an anxiety disorder at age 21 or 26. By comparison, of the children who didn’t have sleep problems at age 9, 33% had an anxiety disorder as young adults, according to the research, which was published in 2005 in the Journal of Abnormal Child Psychology. Scientists caution that some study-sample sizes are small and research is still in its early stages.

Psychiatrists and psychologists say they hope that by addressing sleep problems in childhood, some of the instances of later mental illness can be prevented. There’s a lot parents can do to encourage healthy sleep, including setting a regular bedtime and banning TV watching, Facebook posting and texting in the half hour or so before lights out. Clinicians also have developed effective treatments for poor sleep and are experimenting with some new approaches that teach kids how to reduce the frequency and strength of anxious thoughts that can crop up at night. In general, doctors do not recommend using medication to help kids sleep.

“We think that healthy, optimal sleep may be a buffer against developing anxiety and depression in kids,” says Ronald E. Dahl, a professor at the University of California, Berkeley and a leading researcher on pediatric sleep.

A Good Night

Most parents underestimate the amount of sleep children should get a day. They need:

Infants: 14 to 15 hours
Toddlers: 12 to 14 hours
Preschoolers: 11 to 13 hours
School-age kids: 10 to 11 hours
Teenagers: 9 to 10 hours

Source: The American Academy of Sleep Medicine

Anxiety disorders and depression are the most common mental illnesses: 28.8% of the general population will have an anxiety disorder in their lifetime and 20.8% will have a mood disorder, according to a 2005 study published in the Archives of General Psychiatry. Anxiety disorders emerge early in life: The median age of onset is 11, according to the study. Rates of depression spike in adolescence, too. And those who develop depression young tend to have a more serious disease, with a higher risk of relapse.

Many kids have trouble falling asleep and staying asleep from time to time. Doctors become concerned if the troubles are chronic or often interfere with daytime functioning. “If it consistently takes more than 30 minutes to fall asleep, this is insomnia and it is a problem,” says Anna Ivanenko, associate professor of clinical psychiatry and behavioral sciences at Northwestern University.

According to the National Sleep Foundation’s 2004 Sleep in America poll, 13% of school-age children have difficulty falling asleep at bedtime and 26% of preschoolers seem sleepy or overtired during the day at least a few days a week. The report surveyed 1,473 adults with children 10 and younger in the home. Teenagers tend to have even more sleep issues. About 45% of adolescents ages 11 to 17 get less than eight hours of sleep a night, even though teenagers need between nine and 10 hours. And more than one-quarter of high-school kids fall asleep in school at least once a week, according to another Sleep in America poll from 2006 that surveyed 1,602 sixth through 12th graders and their parents or caregivers.

Scientists aren’t certain as to why poor sleep in childhood increases the risk of anxiety disorders and depression. It could be that sleep problems lead to changes in the brain, which, in turn, contribute to the psychiatric illnesses, they say. Or some underlying issue, partly explained by genetics and early childhood experiences, could be a precursor to both poor sleep and the mental disorders. There is some evidence sleep deprivation weakens the connection between the amygdala (involved in responding to fear) and the prefrontal cortex (which plays a role in executive functioning), “suggesting that sleep deprivation may result in reduced ability to moderate emotional response,” said Alice Gregory, senior lecturer at Goldsmiths, University of London and the lead author of several studies on the relationship between sleep and psychiatric issues, in an email exchange.

Researchers say that before puberty—between the ages of about 9 and 13—is a key time to tackle poor sleep. That’s before the spike in rates of depression and the upheavals of adolescence and while the brain is still very responsive. “The brains of children are far more plastic and amenable to change,” says Candice Alfano, assistant professor of psychology and pediatrics at Children’s National Medical Center in Washington, D.C. Sleep changes dramatically after puberty: Circadian rhythms shift so kids naturally stay up later. With schools starting early, kids often don’t get enough sleep. Academic and social pressures surge, too.

Strategies to encourage healthy sleep in kids

Set a regular bedtime and wake time, even on weekends.
Make the bedroom a dark and quiet oasis for sleep. No homework in bed.
Create a calming bedtime routine. For younger kids: a bath and story. For older kids: Reading or listening to mellow music.
Limit caffeine consumption, especially after 4 p.m.
Ban technology (TV, Web surfing, texting) in the half hour before bed. The activities are stimulating. The light from a computer can interfere with the production of the sleep-promoting hormone, melatonin.
Don’t send kids to bed as punishment or allow them to stay up late as a reward for good behavior. This delivers a negative message about sleep.
Help kids review happy moments from the day. Have them imagine a TV with a ‘savoring channel.’ Relegate anxious thoughts to ‘a worry channel.’

A small study suggested healthy sleep may be able to help protect kids from depression—even those at high-risk because of genetics. (Both anxiety disorders and depression are believed to be partly inherited.) The study, published in 2007 in the journal Development and Psychopathology, found that children who fell asleep quicker and spent more time in the deepest stage of sleep were less likely to develop depression as young adults. A larger body of research shows that improving sleep in kids and adults who already have mental-health problems also leads to a stronger recovery.

There are many relatively simple things parents can do to promote healthy sleep. Make sure kids have a consistent bedtime and wake time, even on weekends. Create a calming bedtime ritual. For young kids, that could mean reading stories, taking a bath and singing songs. For older kids, limit technology during the half hour before bedtime. The light from computers and TVs can actually suppress the body’s production of melatonin, a hormone that promotes sleep, says Judith A. Owens, director of sleep medicine at Children’s National Medical Center. And video games, television and Web surfing are stimulating to the brain. “I can’t tell you how many teenagers wake up at 3 a.m. to make sure they haven’t gotten a text message in the last hour,” she says.

Scientists at the University of Pittsburgh School of Medicine are experimenting with a behavioral treatment called “savoring” to treat anxious kids with sleep problems.

It involves teaching kids to imagine a television with various channels. They then practice developing a “savoring” channel filled with positive thoughts about a fun conversation they had with a friend, for example, or a sleepover they’re looking forward to.

At bedtime, the kids are encouraged to switch from the “worry” channel to the savoring channel. By focusing on positive thoughts at night, researchers hope to improve the children’s sleep, ease their anxiety symptoms and prevent depression.